shinyOAuth (version 0.3.0)

is_ok_host: Check if URL(s) are HTTPS and/or in allowed hosts lists

Description

Returns TRUE if every input URL is either:

• a syntactically valid HTTPS URL, and (if set) whose host matches allowed_hosts, or

• an HTTP URL whose host matches allowed_non_https_hosts (e.g. localhost, 127.0.0.1, ::1), and (if set) also matches allowed_hosts.

If the input omits the scheme (e.g., "localhost:8080/cb"), this function will first attempt to validate it as HTTP (useful for loopback development), and if that fails, as HTTPS. This mirrors how helpers normalize inputs for convenience while still enforcing the same host and scheme policies.

allowed_hosts is thus an allowlist of hosts/domains that are permitted, while allowed_non_https_hosts defines which hosts are allowed to use HTTP instead of HTTPS. If allowed_hosts is NULL or length 0, all hosts are allowed (subject to scheme rules), but HTTPS is still required unless the host is in allowed_non_https_hosts.

Since allowed_hosts supports globs, a value like "*" matches any host and therefore effectively disables endpoint host restrictions. Only use a catch‑all pattern when you truly intend to allow any host. In most deployments you should pin to your expected domain(s), e.g. c(".example.com") or a specific host name.

Wildcards: allowed_hosts and allowed_non_https_hosts support globs: * = any chars, ? = one char. A leading .example.com matches the domain itself and any subdomain.

Any non-URLs, NAs, or empty strings cause a FALSE result.

Usage

is_ok_host(
  url,
  allowed_non_https_hosts = getOption("shinyOAuth.allowed_non_https_hosts", default =
    c("localhost", "127.0.0.1", "::1", "[::1]")),
  allowed_hosts = getOption("shinyOAuth.allowed_hosts", default = NULL)
)

Value

Logical indicator (TRUE if all URLs pass all checks; FALSE otherwise)

Arguments

url

Single URL or vector of URLs (character; length 1 or more)

allowed_non_https_hosts

Character vector of hostnames that are allowed to use HTTP instead of HTTPS. Defaults to localhost equivalents. Supports globs

allowed_hosts

Optional allowlist of hosts/domains; if supplied (length > 0), only these hosts are permitted. Supports globs

Details

This function is used internally to validate redirect URIs in OAuth clients, but can be used elsewhere to test if URLs would be allowed. Internally, it will always determine the default values for allowed_non_https_hosts and allowed_hosts from the options shinyOAuth.allowed_non_https_hosts and shinyOAuth.allowed_hosts, respectively.

Examples

# HTTPS allowed by default
is_ok_host("https://example.com")

# HTTP allowed for localhost
is_ok_host("http://localhost:8100")

# Restrict to a specific domain (allowlist)
is_ok_host("https://api.example.com", allowed_hosts = c(".example.com"))

# Caution: a catch-all pattern disables host restrictions
# (only scheme rules remain). Avoid unless you truly intend it
is_ok_host("https://anywhere.example", allowed_hosts = c("*"))